100% brake system failure ( Can this happen to your SC 430?)
03-22-21, 05:34 AM
#46
Owners should have recourse regarding "total brake failure." Brake systems are designed to be "fail-safe," which means, they fail in a manner which still allows the operator to stop the vehicle. No amount of miles or age should result in a total brake failure. That's why this phenomenon is so rare, because manufacturers go through great lengths to ensure it doesn't happen.
Anyone have a "total brake failure" yet? So far, I haven't seen it. They still had a hard brake. They still had an emergency brake (aptly named?). And they had plenty of warning lights and buzzers letting them know something brake-related failed. Thus, "fail-safe". Notice, though, the complaint article was referring to "brake ASSIST" failures -- I consider that the correct scope. Regardless of scope clarification (100% failure versus partial), brake ASSIST failures are still very scary and severe consequences could occur. No question there.
I think the main disagreement for me is two-fold: (1) members are referring/confusing brake ASSIST failures as "100% brake failures", and (2) they assert that "100% brake failures" should NEVER happen regardless of age or mileage -- thus they conclude brake ASSIST failures should NEVER happen regardless of age or mileage. I consider that a logic fallacy.
For me: (1) brake ASSIST failures are different than "100% brake failures", and (2) brake ASSIST failures WILL happen with age and mileage. Even the recalls/TSBs seem to suggest a 10 year/150k mile limit?
Thanks for the good discussion -- I'll butt out of this debate now. Don't mind me too much, as I'm stressing because it's convertible weather and my SC is out of commission
because it decided to spray fuel all over the back of my hot engine and catalytic convertors! Still waiting for my fuel pulsation dampers to arrive.
The following 2 users liked this post by degmla:
daddiojigg (03-22-21),
jimisbell (04-12-21)
03-22-21, 05:49 AM
#47
No, don't pull anything apart. Just push the grommet to the side and feel (or see if you can) for excessive rust. When I checked my old LX, it was significant. All you're doing is checking to see of those terminals are corroding. And, the grease (I think I used the battery terminal red gel stuff) is just trying to prevent moisture-induced corrosion. I think the rubber grommet is intended to prevent moisture and/or shorting of those two terminals (they are the +/- for the big brake motor), but it seems that, SOMETIMES, it holds moisture and causes severe corrosion. Since corrosion is still electrically conductive, eventually a failure or erratic failure of the brake motor could occur.
Make sense?
Words I've rarely used during "car talk"!
03-22-21, 06:13 AM
#49
03-22-21, 09:15 AM
#50
Lexus Test Driver
See pics in posts #35 and #37. If I were fancy and intelligent, I could probably figure out how to provide a link! Thankfully, I'm neither!
No, don't pull anything apart. Just push the grommet to the side and feel (or see if you can) for excessive rust. When I checked my old LX, it was significant. All you're doing is checking to see of those terminals are corroding. And, the grease (I think I used the battery terminal red gel stuff) is just trying to prevent moisture-induced corrosion. I think the rubber grommet is intended to prevent moisture and/or shorting of those two terminals (they are the +/- for the big brake motor), but it seems that, SOMETIMES, it holds moisture and causes severe corrosion. Since corrosion is still electrically conductive, eventually a failure or erratic failure of the brake motor could occur.
Make sense?
No, don't pull anything apart. Just push the grommet to the side and feel (or see if you can) for excessive rust. When I checked my old LX, it was significant. All you're doing is checking to see of those terminals are corroding. And, the grease (I think I used the battery terminal red gel stuff) is just trying to prevent moisture-induced corrosion. I think the rubber grommet is intended to prevent moisture and/or shorting of those two terminals (they are the +/- for the big brake motor), but it seems that, SOMETIMES, it holds moisture and causes severe corrosion. Since corrosion is still electrically conductive, eventually a failure or erratic failure of the brake motor could occur.
Make sense?
I use it on all automotive electrical connections to include anything around my house exposed to the elements...I have televisions in my pool area and I have used this product on the electrical outlets.
I also use the battery terminal spray as mentioned above.
Last edited by Bgw70; 03-22-21 at 09:19 AM.
03-23-21, 09:09 PM
#53
Instructor
Thread Starter
Guys
not sure how you “ push “ the grommet aside to see if it is leaking
And then reseal while the MS ABS is still in the car.
Can someone with some video skills share?
the pics from #35 and # 37 only show a MS that is
removed and 2 wires that looks corroded
thanks
not sure how you “ push “ the grommet aside to see if it is leaking
And then reseal while the MS ABS is still in the car.
Can someone with some video skills share?
the pics from #35 and # 37 only show a MS that is
removed and 2 wires that looks corroded
thanks
03-24-21, 04:25 AM
#54
Maybe I'll video something when I go to replace my fuel pulsation dampers.
03-24-21, 04:59 AM
#55
Mercedes-Benz has a similar issue with some of their cars. I have an 03 SL500 and experienced failure of the supplemental braking system at 55 mph. One moment the brakes were working as designed the next it was all leg muscle trying to stop the car. Scary to say the least but I did get it stopped without hitting the vehicle in front of me that suddenly braked to avoid a dog. Mercedes had been receiving notices of this happening over the years and in 2018 extended the warranty on the SBC system another 20 years and unlimited mileage. This included reimbursement for those that replaced the system during the time there was no warranty. Repair bills for this typically are 3500 or so.
Similar to the airbag recall on our SC430s, dealerships check the cars, repair and replace components while providing a loaner vehicle. When I had my SL500 done, a part had to come from Germany. I was in the 600 loaner for a month.
I encourage everyone to report these issues to Lexus and the NHSTA. If the numbers show it, there will be a recall and remediation efforts. In the meantime, know that you can stop your car, though not as usual. Drive it and enjoy it. Do pay attention to maintenance and change the fluid.
Similar to the airbag recall on our SC430s, dealerships check the cars, repair and replace components while providing a loaner vehicle. When I had my SL500 done, a part had to come from Germany. I was in the 600 loaner for a month.
I encourage everyone to report these issues to Lexus and the NHSTA. If the numbers show it, there will be a recall and remediation efforts. In the meantime, know that you can stop your car, though not as usual. Drive it and enjoy it. Do pay attention to maintenance and change the fluid.
03-24-21, 05:41 AM
#56
Mercedes-Benz has a similar issue with some of their cars. I have an 03 SL500 and experienced failure of the supplemental braking system at 55 mph. One moment the brakes were working as designed the next it was all leg muscle trying to stop the car. Scary to say the least but I did get it stopped without hitting the vehicle in front of me that suddenly braked to avoid a dog. Mercedes had been receiving notices of this happening over the years and in 2018 extended the warranty on the SBC system another 20 years and unlimited mileage. This included reimbursement for those that replaced the system during the time there was no warranty. Repair bills for this typically are 3500 or so.
And, for the air bags, again, that was already recognized as a problem early on, right? And, indeed, it had documented fatalities/serious injuries associated with it? Thus, it continues its saga as well.
However, brake assist failures initially occurring on vehicles that are ~15 years old and ~150k miles don't yet strike me as a 'similar issue'.
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jimisbell (04-12-21)
03-24-21, 06:09 AM
#57
Lexus Test Driver
03-24-21, 06:30 AM
#59
But, to be fair, that system was initially recalled within a few years of production, right? Like, a ~2006 recall on a 2003 car? So, it seems it was already recognized as a problem area. Then after another 10+ years of continued problems and continued complaints, they extended their initial recall? This is all I gleaned from a quick review.
And, for the air bags, again, that was already recognized as a problem early on, right? And, indeed, it had documented fatalities/serious injuries associated with it? Thus, it continues its saga as well.
However, brake assist failures initially occurring on vehicles that are ~15 years old and ~150k miles don't yet strike me as a 'similar issue'.
And, for the air bags, again, that was already recognized as a problem early on, right? And, indeed, it had documented fatalities/serious injuries associated with it? Thus, it continues its saga as well.
However, brake assist failures initially occurring on vehicles that are ~15 years old and ~150k miles don't yet strike me as a 'similar issue'.
I reference the airbag just as an example of thing already happening with the SC. Still believe in reporting issues, enjoying the car and good maintaince.
The following users liked this post:
degmla (03-24-21)
03-24-21, 06:36 AM
#60
I encourage everyone to report these issues to Lexus and the NHSTA. If the numbers show it, there will be a recall and remediation efforts. In the meantime, know that you can stop your car, though not as usual. Drive it and enjoy it. Do pay attention to maintenance and change the fluid.